ELI5: Explain Like I'm 5

Arithmetic zeta function

Okay, so do you remember how we can add numbers together? Like 2+2=4 and 3+1=4? Well, imagine if we tried to add up all the numbers from 1 to infinity. That’s a lot of numbers, right?

The arithmetic zeta function helps us figure out what happens when we add up all those numbers. It tells us what we get when we add 1 + 2 + 3 + 4 + 5 + … all the way to infinity.

Now, this might seem impossible, but clever mathematicians have figured out a way to make this easier. They take all the prime numbers and raise them to different powers, and then add up all those answers. This gives us the arithmetic zeta function.

For example, let’s take the first few prime numbers: 2, 3, 5, 7, 11, and so on. We can raise each of these prime numbers to different powers, like 2^1, 3^2, 5^3, 7^4, 11^5, and so on. Then we add up all those answers.

When we do that, we get a really interesting number that tells us about all the numbers we added up from 1 to infinity. This number is the arithmetic zeta function.

The arithmetic zeta function is used in lots of different areas of math, like number theory and algebraic geometry. So even though it might seem complicated, it’s actually a really important concept!